Method of evaporation and apparatus therefor.



N. H. HILLBR.

METHOD 0F EVAPORATION AND APPARATUS THEREFOR.

APPLICATION FILED DEO.3,1909.

Patented Apr. 2 6, 1910.

UNirnDrsTArns PAriNr oFFioE.

NIC-oLAI-AiLl-irrHimsa,s or lCARBONDALE, PENNSYLVANIA.

MnTnonoFjEvaPoRA'rroN AND APPARATUS THEREFOR.

To all whom 'it may concerns Be it known that I, NrcoLArH. HILLnn, a

lcitizen'of the UnitedStates of America, and

a resident of Carbondale, county of Lackawann'a, State of Pennsylvania, have invented a certain new and useful Method of Evaporation and Apparatus Therefor, of which -tliefollowing is a specification.

My invention relates to a. method of evaporation and apparatus therefor, and is particularly intended for the production of pure distilled Water such as is desired for the making of artificial ice, but is also appli -cable to the productionzof drinking 'water' on shipboard and elsewhere, where puritif cation of-water byA distillation is desired,

e' also for the distillation vof other liquids..

My invention is particularly applicable for. uses in connection with `absorption re- .frigeration apparatus, and comprises a combination of distillation` apparatus and absorptionxrefrigeration apparatus, wherein steam formed in the apparatus is supplied to the heated coils of the generator of the absorption apparatus,- the condensate' from said coils ybeing* assed to the vfeed lwater heater of the distillation. apparatus and there mingled with water from other sources.

The invention hereindescribed embodies improvements on the method of and apparatus for evaporation, set forth in my ap-V plication led Feb. 20, 1909, Sr. No. 479,049, wherein I have shown anevapor'ator supplying steam to the coils of the generator of an absorption refrigeration apparatus and to the auxiliaries of such refrigeration apparatus, together with means for supple- .menting such steam. supply, when desired,

by steam from a main steam Aline, the water condensed in the feed water. heater and in the coils of the said generator being collected and used for ice making or for other purposes for which pure Water is desired. In

the apparatus herein' described a similar arrangement of apparatus is employed, and to obtain further economy iii the use of steam, I employ a progressive feed water heater for supplying feed water to the boiler from which steam for the operation of `the evaporator and for the mainstream line is obtained, water being heated in this feed water heater, not only by steam from saidv boiler, but also by water condensed in the evaporator and absorptionapparatus generator and which is at a temperature higher than it need be for slipply to the' reboiler of the Sle'lc.tion of Letters Patent. Patented Apr.. 26,. 1910. Applicationaia-rgember s, 1909. seiai No. 531,164. i

apparatus. Iv thereby effect notable economy in the use of steam in the apparatus` As a method, my invention comprises frigeration apparatus or other user of lowV pressure steam; the su ply of the water of condensation from 'suc generator, and the water formed by condensation of steam from the primary source of supply, to appropriate portions of a progressive feedA Water eater; the supply of water of somewhat lower temperature than the water so su plied, from the feed water heater to t ereboiler or other point to which purified iwater is to be delivered; the further heating of water in the feed water heater by steam, and the supply of hot waterV by said feed Water heater to the primary `steam generator. As an apparatus, my invention comprises combinations of apparatus whereby the process above referred to may be carried out.

The objects of my invention are, to purify water by evaporation and condensation, with a very small consumption of steam, or other source of heat supply, and with simple, comp act, reliable and relatively inexpensive apparatus of standard types; and to make the apparatus as simple and inexpensive as possible. I I

In the accompanying drawing I illustrate pumps or auxiliaries to the heating diagrammatically apparatus embodying my invention, and adapted for carr in out the method of evaporation and puri, cation herein described.

In said drawing, 1 designates a boiler or other suitable source of steam which, for the purposes of this specification, may be termed high pressure steam; 2 designates an evapo i'ator; 3the generator of an absorption refrveration apparatus; 4 a hot well, from V which the water t'obe purifiedisftaken; 5, v a feed pump; 6 and-7, auxiliaries of the absorption refrigeration apparatus;` 8, a feed water heater; 9 and 10, traps through'which,

water is supplied to the reboiler; and 11, a reboiler.

Other parts 'of the apparatus, such as pipes, valves, etc., will be referred to from time to time, in describing the operation of the apparatus in carrying out the method above referred to.'

In carrying out the said method, water'is drawn from the vhot well, 4, by the feed pump 5, through a pipe 12, and 1s delivered through a pipe 13 into the colder or entrance portion of the feed water heater 8. Steam of high pressure passes from boiler 1, through a main steam line 14, into the hot'or exit end of the feed water heater 8, the

water to be heated and the steam or Water to do the heatin flowing through separate conduits of tlus heater, in o posite directions, the steam being fina y condensed therein. The water heated .in this feed Water heater passes, through a pipe 15, to tlie boiler A1, and through a pipe 16 to the evaporating chamber 17 of the evaporator 2. Steam to operate this evaporator is supplied from the main steam line 14, by a pipe 18 connected tothe heating chamber 19 of the evaporator 2. Steamproduced in the evaporator passes through a pipe 20, to the feed pump 5, and auxiliaries 6 and 7, serving to operate said pump and auxiliaries, the exhaust steam froml said pump and auxiliaries passing through a pipe 21 to the coils of the generator 3 of the absorption refrigeration apparatus. The water 4condensed in tlie'coils of said generator passes through a pipe 22 and trap 9, into an intermediate section 24 of the feed water heater' 8. I have shown said feed water heater as composed of sections 23, 24, 25 and 26, each composed gf `a plurality of pipe sections connected in series, a sihgle feed waterpipe 27 passing in 'series through these sections, and being connected at its lower end to y pipe 13 and at the other end to pipe 15. A continuous double pipe heater, a type well known in the art of feed water heaters), would be in a broad sense an equivalent of the sectional feed water heater illustrated. The water condensed in thechamber 19 of the evaporator 2 passes through a pipe 28 and trap 10, into another intermediate section 25 of the feed water heater 8,A and the Water condensed in section 26 ofthe feed .water heater passes through a pipe 38 into the same trap 10 and so into heater section 25. Valves 29 and 30, controlled by floats of traps 9 and fO, respectively, control the passage of Water from heater sections 24 and 25, through a pipe 31, into reboiler l1; and

-the gas-freed water from this reboiler 'passes .through pi e 32' into the lowermost section,.

23, oft-'the eed Water heater, and thence out through a pipe 33. From this it will be seen that the feed water, in passingvthrough the pipe 27 of the feed water heater 8, is heated progressively by exchange of heat from fluids of progressively higher temperature. It will be heated, first, in section 23, bywater from the reboiler having e, temperature of say 210 degrees ahrenheit (i. e., a temperature somewhat less than the boiling oint of water at atmospheric pressure) it will be heated next, in section 24, by water from the generator 3 having a temperature of say 267 degrees Fahrenheit; it -Will be heated next in section 25 by Water from the evaporator 2, havin a temperature of say 350 degrees F.; and 1t will be heated, finally, in section 26, by steam from line 14, having a temperature of say-350 degrees F.

I am aware' that it has been proposed heretofore yto distil water in'a` succession of evaporators `the water evaporated in4 each but the last of the* series being condensed in the next .the nc'xt; the water condensed .in the several of the series, the succession of evaporators evaporators being collected in a common pipe line and thence lpassed through a heat exchanger, wherein such water` imparts heat to lncomlngraw Water. thence supphed to a vboiler as feed watenV In such a system, the

water condensed in thel several evaporators will naturally be 4at a higher temperature in each but the last evaporator than in the` evaporator orevaporators operated at lower pressure; yet the condensates from these various evaporators, notwithstanding their dif-v ferent temperatures (in most cases above the boiling polnt of water at'atmospheric pres sure) are mingled in a common collecting line and passed through a single heat ex' changer. It nccessarilyfollows that there is l much revaporation in thiscollecting line, and much loss of heat and ofpurified water for this reason, and: that thewater cannot be dclivcnd to the heat exchangerat above 212 degrees' F. (the last evaporator ofthe series being operated, of course, at'about atmsheric pressure), and that the incoming water cannot be heated to more than 212 degrecs F. But in the apparatus illustrated and described herein, since the feed water heater is connected separately to the several sources of supply of heatinguid of differL ent temperatures, and since these different connections are to different parts ofthe feed water heater, the .incoming f eed water may be heated to nearly the temperature of the steam in the boiler 1, and without loss of heat by unnecessary evaporation.

A numerical example will serve to make st ill learerthe important gain in economy due to this invention. Supposing the pressure in boiler 1 to be 1 20 lbs. per square inch, the steam in line 14 will have a temperature of about 350 degrees F., and the condensate discharged from-chamber 19 of the evaporator and section-26` of the feed water heater will have about the same temperature. There will be some drop in pressure from the steam line 1J( to the secondary steam' line 2U. so that the pressure in said line may be- 'l`he exhaust steam.

supposed to be 90 lbs. from the pump 5 and auxiliarieso and will have a pressure of say lbs. and the water condensed -in the coils ot' generator 3 and supplied to section 24 of the feed water heater will have a temperature of about. 2157 The water from the ieboiler will have lated passage o'f steam from line 14 to line 20; and since the 'exhaust from pump 5 and auxiliaries and 7 maynot be suiiicient for the operation of generator 3, a reducing valve is, provided to permit regulated passage of steam from line 20 to line 21. A For supplying 100 lbs. of water at the reboiler, the steam consumption, at the pressures assumed above, will be about as followsz-l Live steam to heater sec- 7. lbs.

tion 26-1-1. Live steain` to evaporatori). 32.4 L ive steam, line 14 to liue 20 -8.1'

Total live steam-- (38. 1

The exhaust steam supplied by pump 5 and auxiliaries Gand 7 to the generator will amount toabout 31.9 lbs. Section 26 of the heater 8, and the evaporator 2, will together, therefore. supply to the pipe 31 about 40 lbs. of Water, which will have been cooled in the heater from about 350 F. to about 24() F.; and 'generator 3 Will supply to section 24 of the heater, and so to pipe 3l, about (i0 lbs. of water (28.1 plus 31.9) which will have been cooled iii the heater to about 178 F.; so that the mean temperature of the water supplied by pipe 31 to the reboiler'n-'ill be about'215 F.-a temperature just about sutiiciently higher than the boiling point of wat-er at atmospheric pressure tor permit the reboiling necessary to drive otll gases remaining in the water when it reaches the reboiler. There is also some waste .n the reboiler, due to the necessary outflow ot some water through the livered at 33. for (38.1 lbs. of steam supplied pure water supplied, in proportion to the weight of steam used, may also be made by using a somewhatI larger evaporator than indicated in the above figures. Supposing the evaporator used to be one capable of evaporating 40 lbs. 'of steam in the unit of time chosen for comparison, it will probably use about 13 lbs. of live steam from pipe 14 in I doing so; and the supply of +10 lbs. of steam by the evaporator to line 2O will reduce to 2O lbs. the additional amount of steam required to be supplied from line let to line 20 through valve 34, and consequently the total of live steam used will be increased to about- 70 lbs., while they total amount of distilled water supplied to the reboiler will be increased to about 110 lbs. therefore, that a slight increase in the size of the evaporator increases notably the econ'- oniy of the apparatus.

The'supply of feed water to the evaporator 2, from pipe line 15, is controlled by an automatic'float valve 37, the float chamber of whichis connected to the water space of may be understood to be diagrammatic representations of: turbine-driven a paratus.

It will be seen,`

of these parts 5, 6 and 7, in the drawings,

One great advantage of the use o turbinedriven pumps and other vauxiliaries in Water purifying apparatus such as this, is that tur'- ines dp not require internal lubrication, as do reciprocating engines, and soin I,such turbines the steam does not become 'contaminated with oil. The fifteen per cent. waste of water, in the reboiler, to allow for skimming and other losses at the reboiler, made in the above calculations, is ample to cover the Waste necessary when pump 5 and auxiliaries G and 7 are operated by reciprocating engines and consequently mingles more or less lubricatin r oil with the steam. By using turbineriven pumps and other auxiliaries, the waste at the reboiler will customarily be much less than fifteen per-cent. and in such eases the, apparatus will show corresponding increased economy. Pump 5 and auxiliaries and 7, might also, obviously, be operated electrically with the same advantages.

lVhat I claim isz- 1. The method of evaporation and purifi- Vcation herein dcscribed,'comprising produc.

evaporator by exchange of heat with and condensation of a portion of the high pres sure vapor produced as described, doing Work with the lower pressure vapor so produced and condensing the same, and heating -a feed supply of liquid for said boiler by exchange of heat successively with the condensate of the ow pressure vapor, with the condensate from the evaporator, and with another portion ot' the high pressure Vapor.

2. The method of evaporation and purifi- .cation herein described, comprising produc;

sure vapor.

3. The method of evaporation and purifi-V cation herein described, comprisingproducing high pressure vapor of the liquid to be purified by evaporation under pressure in a suitable boiler, evaporating another body of said liquid under lowerI pressure in a suitable evaporator by exchange of heat with and condensation under pressure of a portion ot` the high pressure vapor produced as described, condensing under a lower pressure the lower pressure vapor so produced and heating a feed supply of liquid for said boiler by separate exchange ot' heat with the two condensates mentioned, each at about its pressure ot' condensation.

4. The method of evaporation and purifi- .cation herein described, comprising producing high pressure vapor of the liquid to be purified by evaporation underl ,pressure in a suitable boiler` evaporating another body of said liquid under lower pressure in a suitable evaporator by exchange of heat with and condensation under pressure of a portion of the high pressure vapor produced as described, condensing under a lower pressure the lower pressure vapor so produced and heating a feed supply of liquid for said boiler by separate exchange of heat with the two condensates mentioned, each at about. its pressure of condensation, reboiling the 'cooled condensates after such ,exchange of heat, and exchanging heat between the reboiled liquid andthe feed supply, prior to heating of said feed supply by said condensates.

5. Evaporating and condensing apparatus comprising a primary vapor generator, adapted to evaporate under high pressure, a secondary evaporator connected to Isaid and karrange to evaporate at a lower.v pressure, by exchange of heat withand lcondensation of vapor produced by said primary evaporator, powerV generating means harranged to be operated by the vapor from said secondary evaporator, means for'condensing the exhaust from said power enerating means, and a heater for the fee supply of said primary generator arranged to exchange heat between such feed supply and the condensates of said'secondary. evaporator and' said condensing means, under di, ferent pressures.

6. Evaporating' and condensing apparatus comprising a -primary vapor. generator, adapted to evaporate under high pressure a secondary evaporator connected to said primary evaporator to be :operated thereby and arranged to evaporate at. alower pressure, by exchange of heat with and condensa.-

tion of lvaporproduced 'by said primary evaporator, power generating means arranged to be operated by the vapor from said lseconda-ry evaporator, means for condensing the exhaust from said power generatin means, and a' heater for the feed supply o said primary generator arranged to.l ex- .primary eva' orator to be operated thereby l change heat between such feed supplyand the condensates of saidsecondary evaporator and said condensingmeans, under different pressures, a reboiler, means for conveying the cooled condensates from said-heater to said reboiler and vtraps cont/rolling the delivery of said condensates to said :reboiler and operated by the said condensates in passing to said heater,and arranged to maintain each such condensate under substantially its pressure of condensation while inthe heater.

7. Evaporating and condensing apparatus comprising a. primary vapor generator, adapted to evaporate under high pressure, a secondary evaporator connected to said primary evaporator to be'operated thereby and arrangedqto eva orate at aV lower ressure, byexchange of eat with and con ensation rator, power generating means arranged to be operated by the vapor from said secondary evaporator, means for'- condensing the of vapor producedI by said primary evapo y exhaust from said powergenerating means, y l and a heater for the feed supply ofsaid primary generator arranged to exchange .heat

between such feed supply andthe eendensates of saidf'secondary evaporator and said condensing means, under different ressilres,

a reboiler, means'for conveying' t e cooled Y condensates from said heater. to said reboiler, andtraps controllin the delivery of said -condensates' to said re oiler and operated by the said condensates in passing to said heater, and arranged to maintain each such condensate Vunder substantially its pres sure of condensation while in the heater, and means for conveying the reboiled liquid from said reboiler to said heater at a point in advance of the point where the said condensates are received in said heater.

8. Evaporating and condensing apparatus comprising a primary vapor generator adapted to evaporate under high pressure, a secondary evaporator connected to said primary evaporator to be operated thereby, and .arranged to evaporate at a lower pressure by exchange of heat with and condensation of vapor produced by said primary evaporator, power generating means arranged to be operated by the vapor from said secondary evaporator, a generator of an absor )tion rcfrifrera'tion apparatus arranged to Ibe operated by, and to condense, the exhaust from said power generatin means, and a heater for the feed supply o said primary generator arranged to exchange heat between such 2.0 feed supply and the coiidensates of said secondary evaporator and said `condensing means, under differentpressures. 9`.' Evaporating and condensing appara- -tus comprising a 'primary' vapor generator .A adapted to evaporate underhigh pressure, a

secondary evaporator connected to said pri mary evaporator to be operated thereby, and arranged to evaporate at a lowerl pressure by exchange of heat with and condensation' of 30 vapor produced by said primary evaporator,

power generating means arranged to be operated by the vapor from said secondary evaporator, a generator of an absor )tion icfrigeration apparatus arranged to e.l operated by, and to condense, the-exhaust from said power generator means, and a heater for the feed supply of Said primary genera# tor arranved to exchange heat between such feed suppy and the condensates of said sec- 40 ondary evaporator and said condensing means, under different pressures, a reboiler,

means for conveying the cooled condensates from said heater to said reboiler, and traps controlling the delivery of said condensates to said reboiler and operatedI by the said condensates in passing to said heater, and

arranged to maintain each such condensate undersubstantially its pressure of condensation while in the heater. l

10. Evaporating and condensing apparatus comprising a primary vapor generator adapted to evaporate under high pressure, a

secondary evaporator connected to said primary evaporator to he operated thereby, and

arranged to evaporate, at a lower pressure by exchange of heat with and-condensation of vapor produced by said primary evaporator, power generating means arranged to be operated by the vapor from said second- 50 ary evaporator, a generator o f an absorption refri eration apparatus arranged to be operated y, and to condense, the exhaust from said power generator means, and a heater from the feed supply of said pri- 5 mary generator arranged to exchange heat between such feed supply and the condensates of said secondary evaporator and said condensing means, under diil'crent pressures, a reboiler, means for conveying the cooled`v condensates from said heater to said reboiler, and traps controlling the delivery of said coiidensates lo said reboiler and operated by the said condensates in passingto said heater, and arranged to maintain each such condensate under substantially its prcs- 7g, sure of condensation whilc in the heater, and means for conveying the rcboiled liquid from said reboiler to said heater at a point, in advance of the point. where the said condensates are received in said heater.

1l. Evaporating and condensing apparatus comprising a primary vapor generator adapted to evaporate under higlipressure, a secondary evaporator connected to said primary evaporator to be operated thereby, and arranged to evaporate at a lower pressure by exchange of heat with and condensation of vapor prodncedby said primary evaporator,

power generating means arranged to be operatcd by the vapor from said secondary evaporator, a generator of an absorption refrigeration apparatus arranged to be operatedV by and to condense the exhaust from said powergenerating means, and a heater forqthc feed supply of said primary geiilerator arranged to exchange heat between such feed supply and the eondensates of said secondary evaporator and said condensingmeans, under different pressures, a pressure reducing valve 'connecting the primary va- 1'00 por generator and the discharge of said secondai'yw'apor generator. and another'pressure ,reducing valve connecting the discharge o'f said secondary vapor generator and the said generator of the absorption refrigeration apparatus.

12. Evaporating and condensing appara-` tus comprising a primary vapor lgenerator adapted to evaporate under high pressure, a secondary evaporator connected to said primary evaporator to be operated thereby, and arranged to evaporate at a lower ressure,

,by exchange of heat with and con ensation of vapor produced by said primary evaporator, power generating means arranged to be operated by theva por from said secondary evaporator, means for condensingr the exhaust from said power generating means, a heater for the feed supply of said primary generator arranged to exchange heat bei12-3 tween such feed sii-pplyandvapor from said primary generator, and means for collecting the condensates rfrom the said heater, the -said evaporator, and the said exhaust.

, 13. Evaporating and condensing ,apparatus comprising a primary vapor generator adapted to evaporate under high pressure, a secondary evaporator connected to said privmary evaporator to be operated thereby, and

arranged to evaporate at a lower pressure, by

exchange ofheat with and condensation of vapor produced by said primary evaporator, power enerating means arranged to be op erated y the vapor from said secondary eva orator, a heater for the feed supplyof sai primary generator arranged to exchange heat between such feedsupply and the condensate of said secondary evaporator, and also between such feed supply and the vapor from said primary generator, and means for collecting the condensates from said evaporator, heater, and exhaust.

14. Evaporating and condensing apparatus comprising a primary vapor generator adapted toevaporate under high pressure, a

l secondary evaporator connected to said pritor and said mary evaporator to be operated thereby, and

arranged to evaporate at a lower ressure, by exchange of heat with and con ensation of vapor produced by said primary evaporator, power generating means arranged to be operated by the vapor from said second-V ary evaporator, a heater for the feed supply of said primary generator arranged to exchange heat'between such feed supply and by exchange of heat with and condensation of vapor produced by said primary evaporator, power generating means arranged to be operated bythe vapor from said second- 40 ary evaporator, a sectional heater :for the feed supply of said primary generator arranged to exchange heat between such feed `supply and the condensate from said secondary evaporator, and, in a betweensuch feed supply and theconden` sate from said condensingmeans, and means for collecting theA condensates from said evaporator and condensing means. Y 16.- Evaporating and condensing apparatus comprising a primary vapor generator adapted to evaporate under high pressure, asecondary evaporator 'connected to said primary evaporator to be operated thereby, and arranged to evaporate at a lower pressure, by exchange of heat with and condensation of vapor produced by said primary evaporator, power generating means arranged to be operated by the vapor from said secondary evaporator, a sectional heater for the feed supply of `said primary generatorfarranged to exchange heat between such feed supply and vapor from said primary generator, and, in a. separate Section, between such feed supply and the condensate from p said evaporator, '11nd, in a further section,. between said feed supply and the condensate of said condensing means, and means for' collecting the condensates' from said evaporator, heater and condensing means.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

NIooLAI H;

Witnesses E. M. HoLooMBn, FRANK ORCHARD.

separate section, 45 

